Ricardo A. Tanhoffer

β-Hydroxy-β-methylbutyrate supplementation reduces tumor growth and tumor cell proliferation ex vivo and prevents cachexia in Walker 256 tumor-bearing rats by modifying nuclear factor-κB expression

Cancer cachexia syndrome contributes to wasting and weight loss leading to inefficacy of anticancer therapy. In this study, the anticatabolic agent beta-hydroxy-beta-methylbutyrate (HMB) was supplemented to adult Walker 256 tumor-bearing rats during 8 weeks aiming to determine if tumor burden could be reduced. Male Wistar rats were randomly assigned to nontumor and tumor-bearing groups and fed regular chow or regular chow plus HMB supplemented (76 mg/kg body weight). Beta-hydroxy-beta-methylbutyrate supplementation induced a lower tumor weight and tumor cell proliferation ex vivo, totally prevented glycemia reduction, as well as blunted the increase in the serum lactate concentrations and also preserved glycogen stores in tumor-bearing rats. Reduction in tumor cell proliferation ex vivo was accompanied by increased nuclear factor-kappaB inhibitor-alpha content by more than 100%. In contrast, nuclear factor-kappaB p65 subunit content was suppressed by 17% with HMB supplementation. In conclusion, HMB supplementation, at a similar dose used in humans to increase muscle mass, caused antitumor and anticachectic effects, with tumor-cell nuclear factor-kappaB pathway participation, which might be a potential nutritional strategy in cancer therapy.

Low fish oil intake improves insulin sensitivity, lipid profile and muscle metabolism on insulin resistant MSG-obese rats

BackgroundObesity is commonly associated with diabetes, cardiovascular diseases and cancer. The purpose of this study was to determinate the effect of a lower dose of fish oil supplementation on insulin sensitivity, lipid profile, and muscle metabolism in obese rats.MethodsMonosodium glutamate (MSG) (4 mg/g body weight) was injected in neonatal Wistar male rats. Three-month-old rats were divided in normal-weight control group (C), coconut fat-treated normal weight group (CO), fish oil-treated normal weight group (FO), obese control group (Ob), coconut fat-treated obese group (ObCO) and fish oil-treated obese group (ObFO). Obese insulin-resistant rats were supplemented with fish oil or coconut fat (1 g/kg/day) for 4 weeks. Insulin sensitivity, fasting blood biochemicals parameters, and skeletal muscle glucose metabolism were analyzed.ResultsObese animals (Ob) presented higher Index Lee and 2.5 fold epididymal and retroperitoneal adipose tissue than C. Insulin sensitivity test (Kitt) showed that fish oil supplementation was able to maintain insulin sensitivity of obese rats (ObFO) similar to C. There were no changes in glucose and HDL-cholesterol levels amongst groups. Yet, ObFO revealed lower levels of total cholesterol (TC; 30%) and triacylglycerol (TG; 33%) compared to Ob. Finally, since exposed to insulin, ObFO skeletal muscle revealed an increase of 10% in lactate production, 38% in glycogen synthesis and 39% in oxidation of glucose compared to Ob.ConclusionsLow dose of fish oil supplementation (1 g/kg/day) was able to reduce TC and TG levels, in addition to improved systemic and muscle insulin sensitivity. These results lend credence to the benefits of n-3 fatty acids upon the deleterious effects of insulin resistance mechanisms.

Energy Expenditure in Individuals With Spinal Cord Injury Quantified by Doubly Labeled Water and a Multi-Sensor Armband

BACKGROUND The objective of this study was to determine whether doubly labeled water (DLW) and a multi-sensor armband (SWA) could detect the variation in energy expenditure incurred by a period of increased exercise (EXE) versus a period of high sedentary activity (SED), in individuals with spinal cord injury (SCI). METHODS Eight participants with SCI were submitted to 2 testing periods of energy expenditure assessment: 1) a 14-day phase during which sedentary living conditions were imposed and 2) a 14-day phase during which an exercise training intervention was employed. For each phase, total daily energy expenditure (TDEE) and physical activity energy expenditure (PAEE) were measured by DLW and SWA. RESULTS Mean TDEE assessed by DLW, was significantly higher during EXE versus SED (11,605 ± 2151 kJ·day⁻¹ and 10,069 ± 2310 kJ·day⁻¹). PAEE predicted by DLW was also significantly higher during EXE versus SED (5422 ± 2240 kJ·day⁻¹ and 3855 ± 2496 kJ·day⁻¹). SWA-predicted PAEE significantly underestimated PAEE measured by the DLW during SED and EXE. CONCLUSION DLW is sensitive to detect variation in within-individual energy expenditure during voluntary increase in physical activity in individuals with SCI. SWA failed to detect statistically significant variations in energy expenditure between periods of high versus low activity in SCI.

Exercise, Energy Expenditure, and Body Composition in People with Spinal Cord Injury

BACKGROUND The objective of this study was to verify the long-term effects of exercise on energy expenditure and body composition in individuals with spinal cord injury (SCI), as very little information is available on this population under free-living conditions. METHODS Free-living energy expenditure and body composition using doubly labeled water (DLW) was measured in 13 individuals with SCI, subdivided in 2 groups: (1) sedentary (SED; N = 7) and (2) regularly engaged in any exercise program, for at least 150 min·wk(-1) (EXE; N = 6). RESULTS The total daily energy expenditure (TDEE) was significantly higher in the EXE group (33 ± 4.5 kcal·kg(-1)·day(-1)) if compared with SED group (27 ± 4.3 kcal·kg(-1)·day(-1)). The percentage of body fat was significantly higher in SED group than in EXE group (38 ± 6% and 28 ± 9%). CONCLUSION Our findings revealed that, despite the severity of SCI, the actual ACSMs guidelines for weight management for healthy adults exercise could significantly increase TDEE and BMR and improve body composition in individuals who regularly perform exercise. However, the EXE group still showed a high percentage of body fat, suggesting that a more specific approach might be considered (ie, increased intensity or volume, or combining with a diet program).

Glutamine concentration and immune response of spinal cord-injured rats.

Abstract Background/Objectives: Glutamine plays a key role in immune response. Spinal cord injury (SCI) leads to severe loss of muscle mass and to a high incidence of infections. This study investigated the acute effect of SCI (2 and 5 days) on the plasma glutamine and skeletal muscle concentrations and immune responses in rats. Methods: A total of 29 adult male Wistar rats were divided as follows: control (C; n = 5), sham-operated (S2; n = 5) and spinal cord-transected (T2; n = 7). They were killed on day 2 after surgery/transection (acute phase). Another set was sham-operated (S5; n = 5), spinal cord-transected (T5; n = 7), and killed at day 5 after surgery/transection (secondary phase). Blood was collected; the white portion of the epitrochlearis and gastrocnemius muscles and the red portion of soleus muscles were dissected to measure the glutamine concentration. Gut-associated lymphocytes and peritoneal macrophages were obtained for immune parameters measurements. Results: Glutamine concentration in the plasma, gastrocnemius, and soleus muscles in rats with SCI were significantly reduced but not in the epitrochlearis muscle in the acute (2 days) and secondary (5 days) phases. Phagocytic response was reduced in the acute phase but increased in the secondary phase in rats with SCI. Superoxide production, on the other hand, was significantly increased at days 2 and 5 after SCI, and CD8+ lymphocytes subset decreased significantly on days 2 and 5. Conclusions: Our results showed reduction in plasma glutamine and skeletal muscle concentrations after spinal cord transection. They also suggest that SCI and glutamine reduction contribute to an alteration in immune competence.

The effects of peroxovanadate and peroxovanadyl on glucose metabolism in vivo and identification of signal transduction proteins involved in the mechanism of action in isolated soleus muscle

The insulin-like effects of peroxovanate (POV) and peroxovanadyl (PSV) on rates of lactate formation and glycogen synthesis were measured in isolated incubated soleus muscle preparations. In another experiment rats were made insulin deficient by streptozotocin injection and treated with POV and PSV (0.25 mM) administered in the drinking water and in the course of 7 days glycemia were determined. Also, signal transduction proteins ERK 1 and ERK 2 involved in the insulin signaling were measured in soleus muscle of diabetic rats treated with POV and PSV. Peroxides of vanadate and vanadyl significantly stimulated glucose utilization in soleus muscle preparations in vitro. The stimulation of glycogen synthesis and lactate formation by POV and PSV was similar to insulin stimuli. Rats treated with POV or PSV presented reduction of glycemia, food and fluid intake with amelioration of the diabetic state during the short period of treatment (7 days). POV and PSV modulated ERK1/2 phosphorilation and the insulin administration in these rats caused an addictive effect on phosphorilation state of these proteins.

Fish Oil Supplementation Enhances Pulmonary Strength and Endurance in Women Undergoing Chemotherapy

ABSTRACT We investigated the effect of fish oil (FO) supplementation, at 4 g/day, on the respiratory performance and blood lipid profile of 32 patients with breast cancer at the beginning of chemotherapy. They were randomized into two groups: control (C) and FO supplemented (S). Both groups underwent three respiratory evaluations and blood harvest (before chemotherapy—Day 0, and 30 and 60 days after supplementation). The S group showed a significant increase in the maximal inspiratory and expiratory pressure (P ≤ 0.05 vs. Day 0) and in the maximum voluntary ventilation (P ≤ 0.05). In the treadmill 6-min-walk test, the S group had a significant increase in the walked distance (P ≤ 0.05). Blood lactate concentration was significantly lower in the S group after 60 days, at rest, when compared to C (P ≤ 0.05). Plasma high-density lipoprotein (HDL) cholesterol concentration remained the same after 60 days of supplementation, while in the C group, it decreased significantly (P ≤ 0.05 Day 0 vs. Day 60). Triacylglycerol (TAG) plasma concentration in the S group was lower when compared to the C group (P ≤ 0.05 Day 60S vs. Day 60). Supplementation with FO caused improvement in the respiratory muscle strength and endurance, ameliorated functional performance, and kept TAG, HDL cholesterol, and lactate plasma concentration at normal levels.

Exercise and Shark Liver Oil Supplementation Reduce Tumor Growth and Cancer Cachexia in Walker 256 Tumor Bearing Rats

This study investigated whether exercise associated to shark liver oil supplementation (1 g/kg b.w./day) affects tumor growth, cachexia, lipid peroxidation and proteins expression involved in cell death in Walker 256 tumorbearing rats. Animals were divided into 4 groups: sedentary tumor-bearing (W), sedentary tumor-bearing shark liver oil supplemented (WSL), exercised tumor-bearing (EW) and exercised tumor-bearing shark liver oil supplemented (EWSL). Training sessions consisted of 6 bouts, 30 seconds each with 50% body-weight load attached to the trunk followed by 1 minute of resting (jump training). Five minutes after the finish jump training the exercise groups were subjected to 30 minutes of continuous swimming with a load equivalent to 6% of body weight, 4 times a week during 8 weeks. Tumor cells were injected at the 6th training week and all groups were killed 15 days post inoculation. Tumor weight (g) in W group was of 26.50 ± 1.79 and in the WSL, EW and EWSL was of 14.08 ± 0.91, 15.60 ± 0.55 and 12.60 ± 1.07, respectively. The group W showed hypoglycemia (68.67 ± 2.12 mg/dl), hyperlactacidemia (1.49 ± 0.06 mmol/L), hypertriacylglycerolemia (161.4 ± 9.4 mg/dl) and body weight reduction (13.21 ± 2.25 g) characterizing cachexia state. The groups WSL, EW and EWSL presented reduction of tumor cells proliferation ex vivo, and the production of hydroperoxide and apoptosis was increased. Bax/Bcl-2 expression ratio was increased only in the exercised groups. Shark liver oil supplementation and exercise alone were able in to avoid the installation of cachexia state and also reduced tumor growth, but the association of both cause further effect only in the tumor growth.

Differences of Relative and Absolute Strength of Individuals with Spinal Cord Injury from Able-Bodied Subjects - A Discriminant Analysis

CONTEXT Strength training is one of the most common interventions employed to increase functional independence during rehabilitation of individuals with spinal cord injury (SCI). However, in the literature, different results have been reported in terms of strength modifications after a SCI compared with a control group (CG). OBJECTIVE This study aimed to verify whether discriminant analysis using relative and absolute strength is able to discriminate individuals with different levels of SCI from a CG and to compare strength values of men with different levels of SCI with a CG. DESIGN Cross-sectional study. SETTING Rehabilitation hospital setting. PARTICIPANTS A total of 36 individuals with SCI stratified in tetraplegia (TP; C6-C8), high paraplegia (HP; T1-T6), and low paraplegia (LP; T7-L2), and 12 matched control subjects were enrolled in the study. MAIN OUTCOME MEASURES The subjects performed a maximum strength test of elbow extension/flexion and also shoulder abduction/adduction and flexion/extension in an isokinetic dynamometer. Discriminant analysis was carried out to identify which strength variables would be able to discriminate the TP, HP, or LP groups from the CG. A 1-way analysis of variance was performed to compare peak torque and agonist/antagonist ratio means. RESULTS Shoulder adduction, followed by elbow extension peak torque, was the best variable for discriminating the TP group from the CG (function coefficients: -0.056 and 0.051, respectively, Wilks Λ = 0.41, P ≤ .05). There were no significant differences between the HP group, LP group, and CG. CONCLUSIONS The strength similarity of the paraplegic groups and the CG should not be extrapolated for activities of daily living or sports. The TP group demonstrated lower peak torque for all movements than the CG.

Avaliação isocinética em atletas da seleção brasileira de futebol de 5

INTRODUCCION: La fuerza muscular (FM) de los miembros inferiores es uno de los principales componentes necesarios para acciones especificas durante la practica de futbol de 5 y, cuando presentan niveles insuficientes, los desequilibrios bilaterales elevados o acentuada diferencia en la razon agonista/antagonista (RAA), son factores que contribuyen para el desarrollo de lesiones musculoesqueleticas. OBJETIVO: En este sentido, la propuesta del estudio fue evaluar los niveles de torque maximo, diferencia bilateral en la produccion de fuerza y razon convencional de las musculaturas flexoras y extensoras de la rodilla en diferentes velocidades de ejecucion. METODOS: Participaron en el estudio 11 atletas con discapacidad visual. Los atletas fueron sometidos a evaluacion antropometrica para determinacion de la composicion corporal y sometidos a evaluacion en el dinamometro isocinetico para medir los niveles de desequilibrio muscular y la razon convencional. RESULTADOS: En los movimientos concentricos de la musculatura flexora, se observaron diferencias significativas en el pico de torque (PT) entre los miembros dominantes (MD) y no dominante (MND) en la velocidad de 60°.s-1 y 180°.s-1, en el pico de torque normalizado (PTN) a 60°.s-1 y 180°.s-1 para los musculos extensores. En la RAA se observo diferencia significativa entre MD y MND, y niveles aceptables de RAA en ambas piernas de acuerdo con lo propuesto para el futbol convencional. CONCLUSION: Se espera que los resultados del presente estudio puedan contribuir para los procesos de prevencion, entrenamiento y rehabilitacion de los atletas de futbol de 5, asi como tambien que sirvan como parametros para futuros estudios.